The present invention has as objects a process and a device for attenuating the noise produced at the time of the expansion of a fluid by a valve comprising a plug, or by any other restriction.
It is known that when a stream of fluid is subjected to a process of "throttling" in order to reduce pressure, there is produced, in the case of a compressible fluid, a shock wave giving rise to a noise which is the more intense the higher the speed of the fluid, and, in the case of an incompressible fluid, to a cavitation phenomenon, the magnitude of which is likewise related to the speed of the fluid.
In order to mitigate this disadvantage, it has already been proposed to provide, inside the valves, baffles or labyrinths which assure successive expansions of the fluid while maintaining the flow rate at a lower, substantially constant value. The result of this is that the noise due to throttling and the cavitation are equally reduced. If valves of this type represent considerable progress with respect to the classical valves, they have the disadvantage of being expensive to construct. Besides, the efficiency of the means used is limited by the cavity of said valve.